Just one look and you know your tires are in good condition. The new car has it, but the old one doesn't. You waste so much fuel on a flat tire. But with that you know which tire is low. So worth the money.
Pros
Depending on the identification color for tire pressure gauge. Green indicates the tire pressure is normal. Yellow indicates the pressure is 10% below standard, approximately 5 lbs. Red warns you that the pressure is 25% below standard. Standard at least 10 lbs.